Glacier Surge Research Articles

Distinguishing Glaciers between Surging and Advancing by Remote Sensing: A Case Study in the Eastern Karakoram

The Karakoram has had an overall slight positive glacier mass balance since the end of 20th century, which is anomalous given that most other regions in High Mountain Asia have had negative changes. A large number of advancing, retreating, and surging glaciers are heterogeneously mixed in the Karakoram increasing the difficulties and inaccuracies to identify glacier surges. We found two adjacent glaciers in the eastern Karakoram behaving differently from 1995 to 2019: one was surging and the other was advancing. In order to figure out the differences existing between them and the potential controls on surges in this region, we collected satellite images from Landsat series, ASTER, and Google Earth, along with two sets of digital elevation model. Utilizing visual interpretation, feature tracking of optical images, and differencing between digital elevation models, three major differences were observed: (1) the evolution profiles of the terminus positions occupied different change patterns; (2) the surging glacier experienced a dramatic fluctuation in the surface velocities during and after the event, while the advancing glacier flowed in a stable mode; and (3) surface elevation of the surging glacier decreased in the reservoir and increased in the receiving zone. However, the advancing glacier only had an obvious elevation increase over its terminus part. These differences can be regarded as standards for surge identification in mountain ranges. After combining the differences with regional meteorological conditions, we suggested that changes of thermal and hydrological conditions could play a role in the surge occurrence, in addition, geomorphological characteristics and increasing warming climate might also be part of it. This research strongly contributes to the literatures of glacial motion and glacier mass change in the eastern Karakoram through remote sensing.

Formation of a hazardous ice-dammed glacier lake: a case study of anomalous behavior of Hassanabad glacier system in the Karakoram

Formation of glacier lakes and glacier lake outburst floods (GLOF) are not a new phenomenon in the Karakoram Himalaya. This case study focuses on sudden expansion of Shishper glacier termini and subsequent formation of an ice-dammed glacier lake occupying ~ 3 km moraine following Mochuwar glacier retreat in the Karakoram. A method based on a combination of space (remote sensing) and ground observations is applied to reconstruct spatio-temporal glacier termini change and lake extent. Moreover, the likely glacier-mass losses are determined above and below the Equilibrium Line Altitude (ELA) contours based on recommended values of Accumulation-Area-Ratio and Accumulation-Area-Balance-Ratio for mountain glaciers. Potential implications of glacier surge and ice-dammed glacier lake on downstream infrastructure and hydrological system are assessed. The results show that the Shishper glacier termini advanced 90% from 1980s to 1999 and 78.7% from 1999 to 2019 as compared to 188% and 421% retreat in the Mochuwar glacier termini for the same years, respectively. The current unusual surge of debris-covered Shishper glacier termini created a ~ 152 m deep ice-dammed glacier lake representing a total area increase of 500% over 6 months. The ratio of glacier accumulation to ablation is low for the Hassanabad glacier system, therefore there is a significant influence on forward movement of Shishper glacier termini. Water discharge from the glacier lake increased with increase in summer temperatures causing inundation of part of the Karakoram Highway at Hassanabad village. The current unusual surge of the Shishper glacier can be characterized as type-I as it involves an in-built unsteadiness without any regular intervals due to an unknown mechanism producing very high movement of debris-covered glacial ice and sediments.

Mass balance and a glacier surge of Guliya ice cap in the western Kunlun Shan between 2005 and 2015

Contemporary estimates of glacier changes are necessary to assess the impact of climate change, associated hazards and water resources management. Glaciers in High Mountain Asia (HMA) are mostly retreating except the Karakoram and western Kunlun Shan, confirmed by remote sensing measurements. However, ground validation with precise measurements of these mass balance estimates are scarce. This study selected Guliya ice cap in the western Kunlun Shan to observe its recent changes regarding surface dynamics and mass balance using ASTER DEM of 2005 and 2015. Our findings indicate that one of the north-facing glaciers surged (with no previous surging history) during July and early November 2015, advancing at about 8 m per day on average. The mass balance shows a balance condition +0.01 ± 0.02 m w.e. a−1. The ICESat data (2004–2008) at selected locations compared to dGPS data collected in the field during 2015, indicating a minute difference of 0.03 ± 0.05 m a−1 with ASTER data in the same area. Our findings suggest that Guliya ice cap in the western Kunlun Shan is in equilibrium state following a similar pattern (mass gain or stable conditions) as observed previously.

Formation of long-distance water ice avalanches on Mars

At the high northern latitudes of Mars, there are two impact craters (70.3°N 266.45°E and 67.25°N 249.45°E) with lobate moraine-like ridges (LMLR) on the inner slopes. In addition to these craters, a nearby plain (74°N 95°E) also displays remnants of water ice layered deposits with similar series of lobate ridges. The formation of these ridges has been hypothesized to be caused by either viscoplastic flow of CO2 ice deposits or a catastrophic down-slope movement of an H2O ice massif, which produced long-distance avalanches or fast-running glacier surges. In past climatic epochs, the formation of water ice massifs on high latitudes was possible under low (<20°) planet obliquity. Destabilization of water ice massifs on the craters’ steep inner slopes could lead to down-slope movement, followed by the destruction of the massifs and the production of long-distance water ice avalanches or surges. In this work, we focus on the avalanche formation hypothesis. The down-slope movement of a water ice massif has several possible causes, with the main one being excessive accumulation of water ice on slopes, which then reaches a critical unstable condition. Modeling of long-distance avalanche processes in Martian environments was carried out with Rapid Mass Movement Simulation (RAMMS:AVALANCHE) software, using the graph-analytical method of estimating avalanche velocity and maximum distance. As a result of the modeling, the volume of down-slope movement was defined, confirming the that LMLR were formed by the catastrophic down-slope movement of H2O ice masses in the form of long-distance avalanches.

Investigating the Recent Surge in the Monomah Glacier, Central Kunlun Mountain Range with Multiple Sources of Remote Sensing Data

Several glaciers in the Bukatage Massif are surge-type. However, previous studies in this region focused on glacier area and length changes, and more information is needed to support the deep analysis of glacier surge. We determined changes in glacier thickness, motion, and surface features in this region based on TanDEM-X, ALOS/PRISM, Sentinel-1A, and Landsat images. Our results indicated that the recent surge of the Monomah Glacier, the largest glacier in the Bukatage Massif, started in early 2009 and ceased in late 2016. From 2009 to 2016, its area and length respectively increased by 6.27 km2 and 1.45 km, and its ice tongue experienced three periods of changes: side broadening (2009–2010), rapid advancing (2010–2013), and slow expansion (2013–2016). During 2000–2012, its accumulation zone was thinned by 50 m, while its ice tongue was thickened by 90 m. During 2015–2017, its flow velocity reduced from 1.2 to 0.25 m/d, and the summer velocities were much higher than winter velocities. We conclude that the recent Monomah Glacier surge is thermal-controlled. The subglacial temperature rose to the pressure-melting point because of substantial mass accumulation, and then the increased basal meltwater caused the surge.

Hagen Bræ: A Surging Glacier in North Greenland-35Years of Observations.

We use remotely sensed ice velocities in combination with observations of surface elevation and glacier area change to investigate the dynamics of Hagen Bræ, North Greenland in high detail over the last 35 years. From our data, we can establish for the first time that Hagen Bræ is a surge‐type glacier with characteristics of both Alaskan‐ and Svalbard‐type surging glaciers. We argue that the observed surge was preconditioned by the glacier geometry and triggered by englacially stored meltwater. At present, the glacier is in a transitional state between active and quiescence phases and is not building up to its pre‐surge geometry. We suggest that the glacier is adjusting to the loss of its floating section, general thinning, and changes in fjord conditions that occurred over the study period which are unrelated to the surge behavior. The high temporal resolution of the ice velocity data gives insight to the sub‐annual glacier flow.

Recent Surge Behavior of Walsh Glacier Revealed by Remote Sensing Data.

Many surge-type glaciers are present on the St. Elias Mountains, but a detailed study on the surge behavior of the glaciers is still missing. In this study, we used remote sensing data to reveal detailed glacier surge behavior, focusing on the recent surge at Walsh Glacier, which was reported to have surged once in the 1960s. Glacial velocities were derived using a cross-correlation algorithm, and changes in the medial moraines were interpreted based on Landsat images. The digital elevation model (DEM) difference method was applied to Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) DEMs to evaluate the surface elevation of the glacier. The results showed that the surge initiated near the conjunction of the eastern and northern branches, and then quickly spread downward. The surge period was almost three years, with an active phase of less than two years. The advancing speed of the surge front was much large than the maximum ice velocity of ≈14 m/d observed during the active phase. Summer speed-ups and a winter speed-up in ice velocity were observed from velocity data, with the speed-ups being more obvious during the active phase. Changes in the glacier velocity and the medial moraines suggested that the eastern branch was more affected by the surge. The DEM differencing results showed that the receiving zone thickened up to about 140 m, and the upstream reservoir zone became thinner. These surge behaviors, as characterized by remote sensing data, gave us more detailed insights into the surge dynamics of Walsh Glacier.

Characterization of Kyagar Glacier and Lake Outburst Floods in 2018 Based on Time-Series Sentinel-1A Data

Early recognition of glacial lake outburst floods (GLOFs) is required for timely and cost-effective remedial efforts to be implemented. Although the formation of ice-dammed lakes is known to begin as a pond or river that was blocked by ice from the glacier terminus, the relationship between glacier dynamics and lake development is not well understood. Using a time-series of Sentinel-1A synthetic aperture radar (SAR) data acquired just before and after the lake outburst event in 2018, information is presented on the dynamic characteristics of Kyagar Glacier and its ice-dammed lake. Glacier velocity data derived from interferometry show that the glacier tongue experienced an accelerated advance (maximum velocity of 20 cm/day) just one month before the lake outburst, and a decreased velocity (maximum of 13 cm/day) afterward. Interferometric and backscattering properties of this region provide valuable insight into the diverse glaciated environment. Furthermore, daily temperature and total precipitation data derived from the ECMWF re-analysis (ERA)Interim highlight the importance of the sustained high-temperature driving force, supporting empirical observations from previous studies. The spatial and temporal resolution offered by the Sentinel-1A data allows variations in the glacier surface motion and lake evolution to be detected, meaning that the interaction mechanism between the glacial lake and the associated glacier can be explored. Although the glacier surge provided the boundary conditions favorable for lake formation, the short-term high temperatures and precipitation caused the melting of ice dams and also a rapid increase in the amount of water stored, which accelerated the potential for a lake outburst.

АКТИВИЗАЦИЯ ОБВАЛОВ НА ЦЕНТРАЛЬНОМ КАВКАЗЕ И ИХ ВЛИЯНИЕ НА ДИНАМИКУ ЛЕДНИКОВ И СЕЛЕВЫЕ ПРОЦЕССЫ

We analyzed multi-time satellite images of the Central Caucasus glacial zone and interpreted more than thirty rock avalanche events in the 21st century with a total damage area of more than 25 km 2 (including the collapse zone of the Kolka Glacier disaster). The highest rock and rock-ice avalanche activity is detected in the section of The Greater Caucasus range (northern and southern slopes) with a length of about 20 km between the Bashkara and Kulaktau peaks (16 rock avalanches) and in the section of the Kazbek-Dzhimaray Massif (series of rock avalanches to the surface of Kolka, Suatisi and Devdoraki glaciers). The feature of the rock and ice-rock avalanches is the large runout distance. For 12 events (about 40%) the distance was more than 2000 m. One ice-rock avalanche from the Mount Kazbek (excluding the Kolka Glacier disaster in 2002) reached the runout distance more than 10 km. In some areas, the rock avalanches occurred several times. In particular, a large number of avalanches were in the cirque of the Kolka Glacier; the last of them at the end of 2019. Thrice шт each case, rock avalanches originated from Mount Bashkara, in the cirques of the Murkvam Glacier, the East Shtulu Glacier, and the Devdoraki Glacier. Ice and rock avalanches were the initial stage of the complex process of the Kolka Glacier disaster and following catastrophic glacial debris flow in the Genaldon/Gizeldon River valley in 2002. Also, they were causes of glacier surges, formation of dammed lakes, and debris flows. As a result of the collapse of the hanging glacier and bedrock, the former right tributary of the Kolka Glacier surged to 200 m in 2006. Ice-rock avalanche from Mount Kazbek in 2014 load up the former right tributary of the Devdoraki Glacier and caused its advancing in 2015–2019, at a distance of more than 400 m. The avalanches caused catastrophic debris flows in the Amilishka/Kabakhi River valley in 2014, the Mestiachala River valley in 2019. Rock avalanches can cause outbursts of lakes and debris flows. Two dammed lakes formed as a result of the rock avalanche from the cirque above the Seri Glacier in the Tviberi River valley of the in May 2016. The lakes (total area was more than 0.05 km 2 ) have outburst at the end of August 2017 after heavy rains. Rock avalanches of the 20th century led to an abrupt deceleration in the retreat of the Yusengi, Bartuytsete, East Shtulu and Mosota glaciers. The formation of rock avalanches in the 21st century took place at high altitudes (an average of about 3900 m). Possibly, the reason was associated with an increase of the «0» isotherm and of the high border of the zone of intense frost weathering due to climate warming. Some rock avalanches in the section of the Kazbek-Dzhimarai Massif have been caused by endogenous factors (seismicity and volcanism).

Climate and surging of Donjek Glacier, Yukon, Canada

ABSTRACT Links between climate and glacier surges are poorly understood but are required to enable prediction of surges and mitigation of associated hazards. Here, we investigate the role of snow accumulation, rain, and temperature on surge periodicity, area changes, and timing of surge initiation since the 1930s at Donjek Glacier, Yukon, Canada. Snow accumulation measured in three ice cores collected at Eclipse Icefield indicates that a cumulative accumulation of 15.5 ± 1.46 or 16.6 ± 2.0 m w.e. occurred in the ten to twelve years between each of its last eight surges, depending on ice motion spatiotemporal offset corrections. Although we find consistent snow accumulation between surges, the transient snow line has risen 10.3 m decade−1 vertically since the 1950s, and Burwash Landing weather station records indicate a 0.5°C decade−1 increase in mean annual air temperature since the 1960s. Changes in surface mass balance are accompanied by a consistent surge interval but decreasing surge extent. The three recent surge events initiated in years with the rainiest summers on record. These findings highlight a complex interplay between external (i.e., climate) and internal glacier processes that control surging at Donjek Glacier, with climate having a more direct influence on surge extent than on recurrence interval.

Manifestations and mechanisms of the Karakoram glacier Anomaly.

Global-scale glacier shrinkage is one of the most prominent signs of ongoing climatic change. However, important differences in glacier response exist at the regional scale, and evidence has accumulated that one particular region stands out: the Karakoram. In the past two decades, the region has shown balanced to slightly positive glacier budgets, an increase in glacier ice-flow speeds, stable to partially advancing glacier termini, and widespread glacier surge activity. This is in stark contrast to the rest of High Mountain Asia, where glacier retreat and slowdown dominate, and glacier surging is largely absent. Termed the Karakoram Anomaly, recent observations show that the anomalous glacier behaviour partially extends to the nearby Western Kun Lun and Pamir. Several complementary explanations have now been presented for explaining the Anomaly’s deeper causes, but the understanding is far from being complete. Whether the Anomaly will continue to exist in the coming decades remains unclear, but its long-term persistence seems unlikely in light of the considerable warming anticipated by current projections of future climate.

A 60-year chronology of glacier surges in the central Karakoram from the analysis of satellite image time-series

The glaciers in the Karakoram have recently been studied intensely using satellite data. The related studies investigated a large variety of characteristics (e.g. short and long-term variability in flow velocities, elevation changes and extent) and revealed a behaviour that differs largely from most other regions of the world (e.g. advancing or stable termini and balanced to positive mass budgets over the past decades). In part, this is also due to the high concentration of surge-type glaciers that are particular attractive for remote sensing studies owing to their large short-term changes. Other studies provided a comprehensive overview on the timing of surges in the Karakoram over recent decades. However, limited information is available for the details of the individual surges and what happened before 1989, partly resulting in a wrong understanding of the dynamics. To provide a more extended base of glacier surging in the central Karakoram, this study utilises the abundant declassified satellite images from the Keyhole Mission (Corona and Hexagon) covering the period 1961 to 1980 as well as a historic map from 1937 to decipher the surge history of 27 glaciers since the 1960s and before. The focus is on the detailed description of the pictorial evidence and the conclusions that can be drawn from it. A major outcome of this analysis is that most of the glaciers that have surged recently, have also surged in the 1950 to 1960s as surge cycles are often in the 40 to 60 year range. Combined with further evidence of previous surges, it seems that the so-called ‘Karakoram Anomaly’ is around since at least 200 years. It is also shown that two glaciers that are listed as surging are only expanding, that flow blocking of tributaries plays an important role for several surges, that surging glaciers are mostly free of debris, and that surges show a great variability in regard to surge durations (from 2 to 50+ years) and surge cycles (from 20 to 80+ years). Despite this variability, the pattern of post-surge down-wasting and disintegration is always similar, allowing to derive the timing of surges beyond the available pictorial evidence and also to distinguish a surge from a usual advance which is otherwise difficult.

Evolution of Surge-Type Glaciers in the Yangtze River Headwater Using Multi-Source Remote Sensing Data

A surge-type glacier is a special and dangerous type of glacier, which can advance quickly in a short-time with cycles. Glaciers in the Yangtze River headwater are generally acknowledged to be in a stable state. However, not all of those glaciers are stable. In this paper, five glaciers from the Yangtze River headwater glacier were selected as the experimental subjects, and multi-source remote sensing images were used to study and analyze the surge behavior over the past 30 years. Based on the Landsat series data, ERS-2, and ENVISAT radar data, this paper extracts the glacier centerline information, glacial area information, and glacial flow velocity during different time periods from 1988 to 2018, which are used to monitor the active periods of glacier surges. We found three surge-type glaciers in the study area. The glacial characteristics of the three glaciers showed some drastic changes, they can advance quickly nearly 800 m in active periods, their area change can reach 2.0 × 106 m2, and their flow velocity can suddenly increase by dozens of times. Surging periods and the initiated time of the three glaciers are different, which are locked in 1997, 2003, and 1997–1998. All those surges ended within one to two years. We suggest that the surges in this paper are dominated by hydrological conditions.

The Possible Transition From Glacial Surge to Ice Stream on Vavilov Ice Cap

AbstractSurge‐type glaciers typically undergo cyclical flow instability due to mass accumulation; however, some recent glacier surges have caused irreversible ice loss in a short period. At Vavilov Ice Cap, Russia, surge‐like behavior initiated in 2013 and by spring 2019 the ice cap had lost 9.5 Gt of ice (11% mass of the entire basin). Using time series of surface elevation and glacier velocity derived from satellite optical and synthetic‐aperture radar imagery, we identify a shift of flow pattern starting in 2017 when shear margins formed within the grounded marine piedmont fan. Multiple summer speedups correlate with warmer summers during 2015–2019 and suggest that surface melt may access the subglacial environment. Force balance analysis and examination of the Péclet number show that glacier thinning propagated upstream in 2016–2017, and diffusion became a significant dynamic response to thinning perturbations. Our results suggest that the glacier has entered a new ice stream‐like regime.

Dynamics of Surging Glaciers in the Sugran River Basin (Pamirs)

The results of measurements of the area of surging glaciers in 1974 and 2018 are compared to the data on their areas in 1913. A large decadal (middle-term) variability in the area of basin glaciation is revealed, and it is comparable to the respective secular (long-term) changes. It is shown that in, the southern meridional circulation epoch, despite high summer temperatures, the surging glaciers in the Sugran River basin grew in area due to increased precipitation, supporting the idea about their flood-runoff nature.

A brief communication of shispar glacier surge in 2018, hunza river basin, Pakistan

Glacier surging is a common phenomenon in the Karakoram region, but the driving mechanisms, their occurrence and its relation to a changing climate remain are unclear. In this study, we use Sentinel imagery to quantify advancement of the Shispar glacier during a surge in 2018. Results reveal that Shispar glacier starts rapid surging from Jun 2018. The peak surge is in August 2018. Our data reveal that glacier dammed the Hassanabad stream as result lake formation in upstream area and drainage of the lake also blocked. The surging is continuing and size of newly formed glacier lake is also increasing day by day. Currently, the inflow to lake is very low due to low melting (negative temperature) from the upstream glacier. This inflow of glacier meltwater will be an increase in the summer season, which may grow in lake size and could pose threats to downstream settlements and infrastructure (irrigation channels, powerhouses and bridge at Karakoram Highway (KKH) in the case of a sudden breach in the form of glacial lake outburst flood (GLOF). Currently the damages the powerhouse channel and damage the irrigation channel of Aliabad Hunza. This study recommended that there is a need for monitoring of glacier lake size and blockage area using remote sensing data i.e. satellite images and UAV.

A general theory of glacier surges

AbstractWe present the first general theory of glacier surging that includes both temperate and polythermal glacier surges, based on coupled mass and enthalpy budgets. Enthalpy (in the form of thermal energy and water) is gained at the glacier bed from geothermal heating plus frictional heating (expenditure of potential energy) as a consequence of ice flow. Enthalpy losses occur by conduction and loss of meltwater from the system. Because enthalpy directly impacts flow speeds, mass and enthalpy budgets must simultaneously balance if a glacier is to maintain a steady flow. If not, glaciers undergo out-of-phase mass and enthalpy cycles, manifest as quiescent and surge phases. We illustrate the theory using a lumped element model, which parameterizes key thermodynamic and hydrological processes, including surface-to-bed drainage and distributed and channelized drainage systems. Model output exhibits many of the observed characteristics of polythermal and temperate glacier surges, including the association of surging behaviour with particular combinations of climate (precipitation, temperature), geometry (length, slope) and bed properties (hydraulic conductivity). Enthalpy balance theory explains a broad spectrum of observed surging behaviour in a single framework, and offers an answer to the wider question of why the majority of glaciers do not surge.

Interrogating a Surging Glacier With Seismic Interferometry

AbstractSeismic interferometry can be spectacularly sensitive to temporal changes within the Earth. Zhan (2019, https://doi.org/10.1029/2019GL082411) analyzed 12 years of data from seismic stations situated near Bering Glacier, Alaska, that spanned a 2008–2011 surge. Interferometrically isolated glacier‐crossing surface waves revealed an anisotropic seismic wave speed decrease during the surge. 1‐D and 3‐D modeling suggests pressurized englacial water flow being stored and guided by a network of basal crevasses, thereby sustaining high water pressure at the bed and supporting the high surge velocities. This result is demonstrative of the potential for seismic interferometry and other cryoseismological methods to continuously monitor and reveal changes within dynamic glacial‐hydrological systems.

Characteristics of mountain glacier surge hazard: learning from a surge event in NE Pamir, China

Abnormal glacier movement is likely to result in canyon-type hazards chain, such as the barrier lake of Yarlung Zangbo Grand Canyon formed by glacier debris flow in October 2018 in China. Glacier hazard usually evolves from the glacier surge and may occur in a regular cycle. Understanding the characteristics and process of glacier surge is important for early hazard recognition and hazard assessment. Based on field investigations, remote sensing interpretations and SAR offset-tracking surveys, this study confirms a typical glacier surge in the northeast Pamir, and presents its characteristics and processes. “Black ice” mixed moraines choking uplift and overflowing lateral marine are the most important scenic characteristics, which were formed under the conditions of stagnant glacier downstream and abundant super-glacial moraine. Glacier movement event can be divided into a five-period cycle including quiescent, inoculation, initiation, fracture and decline. This surge event lasted for about 300 days, initiated in February 2015 developed extensive fracturing zone in spring and early summer at maximum velocity of 10±0.95 m/day, declined after August 2015 and recovered to quiescent status in October 2015 for the next inoculation. The average height of glacier “receiving” area increased by 20–40 m with 2.7–3.6×108 m3 ice transferred from glacier “reservoir”, and this volume accumulation again require 50–100 years for glacier mass balance which gives approximately 100 years frequency of the glacier surge. Nevertheless, long-period increase of precipitation and temperature were favorable for the occurrence, hydrological instability is the direct triggering mechanism, and while the Glacier Lake Outburst Flood (GLOF) hazards are unlikely to occur with this surge.

Rate-and-state friction explains glacier surge propagation

The incomplete understanding of glacier dynamics is a major source of uncertainty in assessments of sea-level rise from land-based ice. Through increased ice discharge into the oceans, accelerating glacier flow has the potential to considerably enhance expected sea-level change, well ahead of scenarios considered by the IPCC. Central in our incomplete understanding is the motion at the glacier bed, responsible for flow transients and instabilities involving switches from slow to fast flow. We introduce a rate-and-state framework for the transient evolution of basal shear stress, which we incorporate in glacier simulations. We demonstrate that a velocity-strengthening-weakening transition combined with a characteristic length scale for the opening of subglacial cavities is sufficient to reproduce several previously unexplained features of glacier surges. The rate-and-state framework opens for new ways to analyze, understand and predict transient glacier dynamics as well as to assess the stability of glaciers and ice caps.